1
/* -*- coding: utf-8 -*- */
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* Mandos-client - get and decrypt data from a Mandos server
5
* This program is partly derived from an example program for an Avahi
6
* service browser, downloaded from
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* <http://avahi.org/browser/examples/core-browse-services.c>. This
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* includes the following functions: "resolve_callback",
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* "browse_callback", and parts of "main".
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* Copyright © 2008,2009 Teddy Hogeborn
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* Copyright © 2008,2009 Björn Påhlsson
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* This program is free software: you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@fukt.bsnet.se>.
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/* Needed by GPGME, specifically gpgme_data_seek() */
33
#define _LARGEFILE_SOURCE
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#define _FILE_OFFSET_BITS 64
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
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#include <stdio.h> /* fprintf(), stderr, fwrite(),
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stdout, ferror(), sscanf(),
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#include <stdint.h> /* uint16_t, uint32_t */
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#include <stddef.h> /* NULL, size_t, ssize_t */
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#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
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#include <stdbool.h> /* bool, false, true */
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#include <string.h> /* memset(), strcmp(), strlen(),
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strerror(), asprintf(), strcpy() */
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#include <sys/ioctl.h> /* ioctl */
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#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
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sockaddr_in6, PF_INET6,
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SOCK_STREAM, uid_t, gid_t, open(),
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#include <sys/stat.h> /* open() */
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#include <sys/socket.h> /* socket(), struct sockaddr_in6,
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inet_pton(), connect() */
56
#include <fcntl.h> /* open() */
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#include <dirent.h> /* opendir(), struct dirent, readdir()
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#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
60
#include <assert.h> /* assert() */
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#include <errno.h> /* perror(), errno */
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#include <time.h> /* nanosleep(), time() */
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#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
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SIOCSIFFLAGS, if_indextoname(),
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if_nametoindex(), IF_NAMESIZE */
66
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
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INET_ADDRSTRLEN, INET6_ADDRSTRLEN
69
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
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getuid(), getgid(), setuid(),
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#include <arpa/inet.h> /* inet_pton(), htons */
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#include <iso646.h> /* not, or, and */
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#include <argp.h> /* struct argp_option, error_t, struct
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argp_state, struct argp,
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argp_parse(), ARGP_KEY_ARG,
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ARGP_KEY_END, ARGP_ERR_UNKNOWN */
79
#include <sys/klog.h> /* klogctl() */
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/* All Avahi types, constants and functions
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#include <avahi-core/core.h>
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#include <avahi-core/lookup.h>
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#include <avahi-core/log.h>
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#include <avahi-common/simple-watch.h>
90
#include <avahi-common/malloc.h>
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#include <avahi-common/error.h>
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#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
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init_gnutls_session(),
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#include <gnutls/openpgp.h>
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/* gnutls_certificate_set_openpgp_key_file(),
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GNUTLS_OPENPGP_FMT_BASE64 */
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#include <gpgme.h> /* All GPGME types, constants and
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GPGME_PROTOCOL_OpenPGP,
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#define BUFFER_SIZE 256
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#define PATHDIR "/conf/conf.d/mandos"
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#define SECKEY "seckey.txt"
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#define PUBKEY "pubkey.txt"
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static const char mandos_protocol_version[] = "1";
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const char *argp_program_version = "mandos-client " VERSION;
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const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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/* Used for passing in values through the Avahi callback functions */
123
AvahiSimplePoll *simple_poll;
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gnutls_certificate_credentials_t cred;
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unsigned int dh_bits;
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gnutls_dh_params_t dh_params;
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const char *priority;
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* Make additional room in "buffer" for at least BUFFER_SIZE
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* additional bytes. "buffer_capacity" is how much is currently
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* allocated, "buffer_length" is how much is already used.
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size_t incbuffer(char **buffer, size_t buffer_length,
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size_t buffer_capacity){
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if(buffer_length + BUFFER_SIZE > buffer_capacity){
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*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
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buffer_capacity += BUFFER_SIZE;
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return buffer_capacity;
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static bool init_gpgme(mandos_context *mc, const char *seckey,
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const char *pubkey, const char *tempdir){
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gpgme_engine_info_t engine_info;
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* Helper function to insert pub and seckey to the engine keyring.
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bool import_key(const char *filename){
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gpgme_data_t pgp_data;
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fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
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rc = gpgme_data_new_from_fd(&pgp_data, fd);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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rc = gpgme_op_import(mc->ctx, pgp_data);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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ret = (int)TEMP_FAILURE_RETRY(close(fd));
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gpgme_data_release(pgp_data);
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fprintf(stderr, "Initialize gpgme\n");
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gpgme_check_version(NULL);
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rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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/* Set GPGME home directory for the OpenPGP engine only */
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rc = gpgme_get_engine_info(&engine_info);
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if(rc != GPG_ERR_NO_ERROR){
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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while(engine_info != NULL){
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if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
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gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
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engine_info->file_name, tempdir);
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engine_info = engine_info->next;
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if(engine_info == NULL){
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fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
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/* Create new GPGME "context" */
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rc = gpgme_new(&(mc->ctx));
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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if(not import_key(pubkey) or not import_key(seckey)){
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* Decrypt OpenPGP data.
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* Returns -1 on error
246
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
247
const char *cryptotext,
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gpgme_data_t dh_crypto, dh_plain;
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size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
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fprintf(stderr, "Trying to decrypt OpenPGP data\n");
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/* Create new GPGME data buffer from memory cryptotext */
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rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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/* Create new empty GPGME data buffer for the plaintext */
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rc = gpgme_data_new(&dh_plain);
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if(rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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gpgme_data_release(dh_crypto);
278
/* Decrypt data from the cryptotext data buffer to the plaintext
280
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
281
if(rc != GPG_ERR_NO_ERROR){
282
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
284
plaintext_length = -1;
286
gpgme_decrypt_result_t result;
287
result = gpgme_op_decrypt_result(mc->ctx);
289
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
291
fprintf(stderr, "Unsupported algorithm: %s\n",
292
result->unsupported_algorithm);
293
fprintf(stderr, "Wrong key usage: %u\n",
294
result->wrong_key_usage);
295
if(result->file_name != NULL){
296
fprintf(stderr, "File name: %s\n", result->file_name);
298
gpgme_recipient_t recipient;
299
recipient = result->recipients;
301
while(recipient != NULL){
302
fprintf(stderr, "Public key algorithm: %s\n",
303
gpgme_pubkey_algo_name(recipient->pubkey_algo));
304
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
305
fprintf(stderr, "Secret key available: %s\n",
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recipient->status == GPG_ERR_NO_SECKEY
308
recipient = recipient->next;
317
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
320
/* Seek back to the beginning of the GPGME plaintext data buffer */
321
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
322
perror("gpgme_data_seek");
323
plaintext_length = -1;
329
plaintext_capacity = incbuffer(plaintext,
330
(size_t)plaintext_length,
332
if(plaintext_capacity == 0){
334
plaintext_length = -1;
338
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
340
/* Print the data, if any */
346
perror("gpgme_data_read");
347
plaintext_length = -1;
350
plaintext_length += ret;
354
fprintf(stderr, "Decrypted password is: ");
355
for(ssize_t i = 0; i < plaintext_length; i++){
356
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
358
fprintf(stderr, "\n");
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/* Delete the GPGME cryptotext data buffer */
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gpgme_data_release(dh_crypto);
366
/* Delete the GPGME plaintext data buffer */
367
gpgme_data_release(dh_plain);
368
return plaintext_length;
371
static const char * safer_gnutls_strerror(int value){
372
const char *ret = gnutls_strerror(value); /* Spurious warning from
373
-Wunreachable-code */
379
/* GnuTLS log function callback */
380
static void debuggnutls(__attribute__((unused)) int level,
382
fprintf(stderr, "GnuTLS: %s", string);
385
static int init_gnutls_global(mandos_context *mc,
386
const char *pubkeyfilename,
387
const char *seckeyfilename){
391
fprintf(stderr, "Initializing GnuTLS\n");
394
ret = gnutls_global_init();
395
if(ret != GNUTLS_E_SUCCESS){
396
fprintf(stderr, "GnuTLS global_init: %s\n",
397
safer_gnutls_strerror(ret));
402
/* "Use a log level over 10 to enable all debugging options."
405
gnutls_global_set_log_level(11);
406
gnutls_global_set_log_function(debuggnutls);
409
/* OpenPGP credentials */
410
gnutls_certificate_allocate_credentials(&mc->cred);
411
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
416
safer_gnutls_strerror(ret));
417
gnutls_global_deinit();
422
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
423
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
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ret = gnutls_certificate_set_openpgp_key_file
428
(mc->cred, pubkeyfilename, seckeyfilename,
429
GNUTLS_OPENPGP_FMT_BASE64);
430
if(ret != GNUTLS_E_SUCCESS){
432
"Error[%d] while reading the OpenPGP key pair ('%s',"
433
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
434
fprintf(stderr, "The GnuTLS error is: %s\n",
435
safer_gnutls_strerror(ret));
439
/* GnuTLS server initialization */
440
ret = gnutls_dh_params_init(&mc->dh_params);
441
if(ret != GNUTLS_E_SUCCESS){
442
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
443
" %s\n", safer_gnutls_strerror(ret));
446
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
447
if(ret != GNUTLS_E_SUCCESS){
448
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
449
safer_gnutls_strerror(ret));
453
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
459
gnutls_certificate_free_credentials(mc->cred);
460
gnutls_global_deinit();
461
gnutls_dh_params_deinit(mc->dh_params);
465
static int init_gnutls_session(mandos_context *mc,
466
gnutls_session_t *session){
468
/* GnuTLS session creation */
469
ret = gnutls_init(session, GNUTLS_SERVER);
470
if(ret != GNUTLS_E_SUCCESS){
471
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
472
safer_gnutls_strerror(ret));
477
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
478
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Syntax error at: %s\n", err);
480
fprintf(stderr, "GnuTLS error: %s\n",
481
safer_gnutls_strerror(ret));
482
gnutls_deinit(*session);
487
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
489
if(ret != GNUTLS_E_SUCCESS){
490
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
491
safer_gnutls_strerror(ret));
492
gnutls_deinit(*session);
496
/* ignore client certificate if any. */
497
gnutls_certificate_server_set_request(*session,
500
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
505
/* Avahi log function callback */
506
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
507
__attribute__((unused)) const char *txt){}
509
/* Called when a Mandos server is found */
510
static int start_mandos_communication(const char *ip, uint16_t port,
511
AvahiIfIndex if_index,
512
mandos_context *mc, int af){
516
struct sockaddr_in in;
517
struct sockaddr_in6 in6;
520
char *decrypted_buffer;
521
size_t buffer_length = 0;
522
size_t buffer_capacity = 0;
523
ssize_t decrypted_buffer_size;
526
gnutls_session_t session;
527
int pf; /* Protocol family */
537
fprintf(stderr, "Bad address family: %d\n", af);
541
ret = init_gnutls_session(mc, &session);
547
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
551
tcp_sd = socket(pf, SOCK_STREAM, 0);
557
memset(&to, 0, sizeof(to));
559
to.in6.sin6_family = (uint16_t)af;
560
ret = inet_pton(af, ip, &to.in6.sin6_addr);
562
to.in.sin_family = (sa_family_t)af;
563
ret = inet_pton(af, ip, &to.in.sin_addr);
570
fprintf(stderr, "Bad address: %s\n", ip);
574
to.in6.sin6_port = htons(port); /* Spurious warnings from
576
-Wunreachable-code */
578
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
579
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
581
if(if_index == AVAHI_IF_UNSPEC){
582
fprintf(stderr, "An IPv6 link-local address is incomplete"
583
" without a network interface\n");
586
/* Set the network interface number as scope */
587
to.in6.sin6_scope_id = (uint32_t)if_index;
590
to.in.sin_port = htons(port); /* Spurious warnings from
592
-Wunreachable-code */
596
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
597
char interface[IF_NAMESIZE];
598
if(if_indextoname((unsigned int)if_index, interface) == NULL){
599
perror("if_indextoname");
601
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
602
ip, interface, port);
605
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
608
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
609
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
612
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
615
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
621
if(strcmp(addrstr, ip) != 0){
622
fprintf(stderr, "Canonical address form: %s\n", addrstr);
628
ret = connect(tcp_sd, &to.in6, sizeof(to));
630
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
637
const char *out = mandos_protocol_version;
640
size_t out_size = strlen(out);
641
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
642
out_size - written));
648
written += (size_t)ret;
649
if(written < out_size){
652
if(out == mandos_protocol_version){
662
fprintf(stderr, "Establishing TLS session with %s\n", ip);
665
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
668
ret = gnutls_handshake(session);
669
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
671
if(ret != GNUTLS_E_SUCCESS){
673
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
680
/* Read OpenPGP packet that contains the wanted password */
683
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
688
buffer_capacity = incbuffer(&buffer, buffer_length,
690
if(buffer_capacity == 0){
696
sret = gnutls_record_recv(session, buffer+buffer_length,
703
case GNUTLS_E_INTERRUPTED:
706
case GNUTLS_E_REHANDSHAKE:
708
ret = gnutls_handshake(session);
709
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
711
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
718
fprintf(stderr, "Unknown error while reading data from"
719
" encrypted session with Mandos server\n");
721
gnutls_bye(session, GNUTLS_SHUT_RDWR);
725
buffer_length += (size_t) sret;
730
fprintf(stderr, "Closing TLS session\n");
733
gnutls_bye(session, GNUTLS_SHUT_RDWR);
735
if(buffer_length > 0){
736
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
739
if(decrypted_buffer_size >= 0){
741
while(written < (size_t) decrypted_buffer_size){
742
ret = (int)fwrite(decrypted_buffer + written, 1,
743
(size_t)decrypted_buffer_size - written,
745
if(ret == 0 and ferror(stdout)){
747
fprintf(stderr, "Error writing encrypted data: %s\n",
753
written += (size_t)ret;
755
free(decrypted_buffer);
763
/* Shutdown procedure */
767
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
771
gnutls_deinit(session);
775
static void resolve_callback(AvahiSServiceResolver *r,
776
AvahiIfIndex interface,
778
AvahiResolverEvent event,
782
const char *host_name,
783
const AvahiAddress *address,
785
AVAHI_GCC_UNUSED AvahiStringList *txt,
786
AVAHI_GCC_UNUSED AvahiLookupResultFlags
789
mandos_context *mc = userdata;
792
/* Called whenever a service has been resolved successfully or
797
case AVAHI_RESOLVER_FAILURE:
798
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
799
" of type '%s' in domain '%s': %s\n", name, type, domain,
800
avahi_strerror(avahi_server_errno(mc->server)));
803
case AVAHI_RESOLVER_FOUND:
805
char ip[AVAHI_ADDRESS_STR_MAX];
806
avahi_address_snprint(ip, sizeof(ip), address);
808
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
809
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
810
ip, (intmax_t)interface, port);
812
int ret = start_mandos_communication(ip, port, interface, mc,
813
avahi_proto_to_af(proto));
815
avahi_simple_poll_quit(mc->simple_poll);
819
avahi_s_service_resolver_free(r);
822
static void browse_callback(AvahiSServiceBrowser *b,
823
AvahiIfIndex interface,
824
AvahiProtocol protocol,
825
AvahiBrowserEvent event,
829
AVAHI_GCC_UNUSED AvahiLookupResultFlags
832
mandos_context *mc = userdata;
835
/* Called whenever a new services becomes available on the LAN or
836
is removed from the LAN */
840
case AVAHI_BROWSER_FAILURE:
842
fprintf(stderr, "(Avahi browser) %s\n",
843
avahi_strerror(avahi_server_errno(mc->server)));
844
avahi_simple_poll_quit(mc->simple_poll);
847
case AVAHI_BROWSER_NEW:
848
/* We ignore the returned Avahi resolver object. In the callback
849
function we free it. If the Avahi server is terminated before
850
the callback function is called the Avahi server will free the
853
if(!(avahi_s_service_resolver_new(mc->server, interface,
854
protocol, name, type, domain,
855
AVAHI_PROTO_INET6, 0,
856
resolve_callback, mc)))
857
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
858
name, avahi_strerror(avahi_server_errno(mc->server)));
861
case AVAHI_BROWSER_REMOVE:
864
case AVAHI_BROWSER_ALL_FOR_NOW:
865
case AVAHI_BROWSER_CACHE_EXHAUSTED:
867
fprintf(stderr, "No Mandos server found, still searching...\n");
873
int main(int argc, char *argv[]){
874
AvahiSServiceBrowser *sb = NULL;
879
int exitcode = EXIT_SUCCESS;
880
const char *interface = "eth0";
881
struct ifreq network;
885
char *connect_to = NULL;
886
char tempdir[] = "/tmp/mandosXXXXXX";
887
bool tempdir_created = false;
888
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
889
const char *seckey = PATHDIR "/" SECKEY;
890
const char *pubkey = PATHDIR "/" PUBKEY;
892
mandos_context mc = { .simple_poll = NULL, .server = NULL,
893
.dh_bits = 1024, .priority = "SECURE256"
894
":!CTYPE-X.509:+CTYPE-OPENPGP" };
895
bool gnutls_initialized = false;
896
bool gpgme_initialized = false;
900
struct argp_option options[] = {
901
{ .name = "debug", .key = 128,
902
.doc = "Debug mode", .group = 3 },
903
{ .name = "connect", .key = 'c',
904
.arg = "ADDRESS:PORT",
905
.doc = "Connect directly to a specific Mandos server",
907
{ .name = "interface", .key = 'i',
909
.doc = "Network interface that will be used to search for"
912
{ .name = "seckey", .key = 's',
914
.doc = "OpenPGP secret key file base name",
916
{ .name = "pubkey", .key = 'p',
918
.doc = "OpenPGP public key file base name",
920
{ .name = "dh-bits", .key = 129,
922
.doc = "Bit length of the prime number used in the"
923
" Diffie-Hellman key exchange",
925
{ .name = "priority", .key = 130,
927
.doc = "GnuTLS priority string for the TLS handshake",
929
{ .name = "delay", .key = 131,
931
.doc = "Maximum delay to wait for interface startup",
936
error_t parse_opt(int key, char *arg,
937
struct argp_state *state){
939
case 128: /* --debug */
942
case 'c': /* --connect */
945
case 'i': /* --interface */
948
case 's': /* --seckey */
951
case 'p': /* --pubkey */
954
case 129: /* --dh-bits */
955
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
956
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
957
or arg[numchars] != '\0'){
958
fprintf(stderr, "Bad number of DH bits\n");
961
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
963
case 130: /* --priority */
966
case 131: /* --delay */
967
ret = sscanf(arg, "%lf%n", &delay, &numchars);
968
if(ret < 1 or arg[numchars] != '\0'){
969
fprintf(stderr, "Bad delay\n");
978
return ARGP_ERR_UNKNOWN;
983
struct argp argp = { .options = options, .parser = parse_opt,
985
.doc = "Mandos client -- Get and decrypt"
986
" passwords from a Mandos server" };
987
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
988
if(ret == ARGP_ERR_UNKNOWN){
989
fprintf(stderr, "Unknown error while parsing arguments\n");
990
exitcode = EXIT_FAILURE;
995
/* If the interface is down, bring it up */
996
if(interface[0] != '\0'){
998
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
999
messages to mess up the prompt */
1000
ret = klogctl(8, NULL, 5);
1001
bool restore_loglevel = true;
1003
restore_loglevel = false;
1008
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1011
exitcode = EXIT_FAILURE;
1013
if(restore_loglevel){
1014
ret = klogctl(7, NULL, 0);
1022
strcpy(network.ifr_name, interface);
1023
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1025
perror("ioctl SIOCGIFFLAGS");
1027
if(restore_loglevel){
1028
ret = klogctl(7, NULL, 0);
1034
exitcode = EXIT_FAILURE;
1037
if((network.ifr_flags & IFF_UP) == 0){
1038
network.ifr_flags |= IFF_UP;
1039
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1041
perror("ioctl SIOCSIFFLAGS");
1042
exitcode = EXIT_FAILURE;
1044
if(restore_loglevel){
1045
ret = klogctl(7, NULL, 0);
1054
/* sleep checking until interface is running */
1055
for(int i=0; i < delay * 4; i++){
1056
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1058
perror("ioctl SIOCGIFFLAGS");
1059
} else if(network.ifr_flags & IFF_RUNNING){
1062
struct timespec sleeptime = { .tv_nsec = 250000000 };
1063
ret = nanosleep(&sleeptime, NULL);
1064
if(ret == -1 and errno != EINTR){
1065
perror("nanosleep");
1068
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1073
if(restore_loglevel){
1074
/* Restores kernel loglevel to default */
1075
ret = klogctl(7, NULL, 0);
1097
ret = init_gnutls_global(&mc, pubkey, seckey);
1099
fprintf(stderr, "init_gnutls_global failed\n");
1100
exitcode = EXIT_FAILURE;
1103
gnutls_initialized = true;
1106
if(mkdtemp(tempdir) == NULL){
1110
tempdir_created = true;
1112
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1113
fprintf(stderr, "init_gpgme failed\n");
1114
exitcode = EXIT_FAILURE;
1117
gpgme_initialized = true;
1120
if(interface[0] != '\0'){
1121
if_index = (AvahiIfIndex) if_nametoindex(interface);
1123
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1124
exitcode = EXIT_FAILURE;
1129
if(connect_to != NULL){
1130
/* Connect directly, do not use Zeroconf */
1131
/* (Mainly meant for debugging) */
1132
char *address = strrchr(connect_to, ':');
1133
if(address == NULL){
1134
fprintf(stderr, "No colon in address\n");
1135
exitcode = EXIT_FAILURE;
1139
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1140
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1141
or address[numchars+1] != '\0'){
1142
fprintf(stderr, "Bad port number\n");
1143
exitcode = EXIT_FAILURE;
1146
port = (uint16_t)tmpmax;
1148
address = connect_to;
1149
/* Colon in address indicates IPv6 */
1151
if(strchr(address, ':') != NULL){
1156
ret = start_mandos_communication(address, port, if_index, &mc,
1159
exitcode = EXIT_FAILURE;
1161
exitcode = EXIT_SUCCESS;
1167
avahi_set_log_function(empty_log);
1170
/* Initialize the pseudo-RNG for Avahi */
1171
srand((unsigned int) time(NULL));
1173
/* Allocate main Avahi loop object */
1174
mc.simple_poll = avahi_simple_poll_new();
1175
if(mc.simple_poll == NULL){
1176
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1177
exitcode = EXIT_FAILURE;
1182
AvahiServerConfig config;
1183
/* Do not publish any local Zeroconf records */
1184
avahi_server_config_init(&config);
1185
config.publish_hinfo = 0;
1186
config.publish_addresses = 0;
1187
config.publish_workstation = 0;
1188
config.publish_domain = 0;
1190
/* Allocate a new server */
1191
mc.server = avahi_server_new(avahi_simple_poll_get
1192
(mc.simple_poll), &config, NULL,
1195
/* Free the Avahi configuration data */
1196
avahi_server_config_free(&config);
1199
/* Check if creating the Avahi server object succeeded */
1200
if(mc.server == NULL){
1201
fprintf(stderr, "Failed to create Avahi server: %s\n",
1202
avahi_strerror(error));
1203
exitcode = EXIT_FAILURE;
1207
/* Create the Avahi service browser */
1208
sb = avahi_s_service_browser_new(mc.server, if_index,
1209
AVAHI_PROTO_INET6, "_mandos._tcp",
1210
NULL, 0, browse_callback, &mc);
1212
fprintf(stderr, "Failed to create service browser: %s\n",
1213
avahi_strerror(avahi_server_errno(mc.server)));
1214
exitcode = EXIT_FAILURE;
1218
/* Run the main loop */
1221
fprintf(stderr, "Starting Avahi loop search\n");
1224
avahi_simple_poll_loop(mc.simple_poll);
1229
fprintf(stderr, "%s exiting\n", argv[0]);
1232
/* Cleanup things */
1234
avahi_s_service_browser_free(sb);
1236
if(mc.server != NULL)
1237
avahi_server_free(mc.server);
1239
if(mc.simple_poll != NULL)
1240
avahi_simple_poll_free(mc.simple_poll);
1242
if(gnutls_initialized){
1243
gnutls_certificate_free_credentials(mc.cred);
1244
gnutls_global_deinit();
1245
gnutls_dh_params_deinit(mc.dh_params);
1248
if(gpgme_initialized){
1249
gpgme_release(mc.ctx);
1252
/* Removes the temp directory used by GPGME */
1253
if(tempdir_created){
1255
struct dirent *direntry;
1256
d = opendir(tempdir);
1258
if(errno != ENOENT){
1263
direntry = readdir(d);
1264
if(direntry == NULL){
1267
/* Skip "." and ".." */
1268
if(direntry->d_name[0] == '.'
1269
and (direntry->d_name[1] == '\0'
1270
or (direntry->d_name[1] == '.'
1271
and direntry->d_name[2] == '\0'))){
1274
char *fullname = NULL;
1275
ret = asprintf(&fullname, "%s/%s", tempdir,
1281
ret = remove(fullname);
1283
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1290
ret = rmdir(tempdir);
1291
if(ret == -1 and errno != ENOENT){